INDONESIA is on course to meet its target of 10 million foreign tourists this year as data up to August showed encouraging signs despite a temporary glitch from airport shutdowns across Java and Bali because of volcanic ash.

More than 850,000 foreign tourists arrived in the country in August, up 2.87 per cent year on year and 4.46 per cent compared with the July figure, the Central Statistics Agency (BPS) announced on Thursday.

That boosted foreign-tourist arrivals to 6.32 million so far this year, a 2.7-per-cent year-on-year increase from the January-August 2014 period.

With more than 3.6 million more arrivals needed by year-end to catch up, the Tourism Ministry was upbeat that the last four months of the year would see a pick-up in arrivals, as seen in previous years.

"We aim to welcome 850,000 foreign tourists in September, 1 million each in October and November and 1.1 million in December, thus achieving our 10-million-arrivals target," said VinsensiusJemadu, the ministry's Asia-Pacific promotion director.

This year's 10-million target is part of President Joko Widodo's vision to see annual foreign-tourist arrivals of 20 million by 2019, when his tenure ends.

"We aim to welcome 12 million tourists next year and gradually increase it to 20 million in 2019," Vinsensius said in reference to the ministry's mid-term development |plan.

The government has waived visa requirements for visitors from dozens of countries and intensified overseas promotions to realise the ambitious tourist target.

BPS head Suryamin said this year's monthly tourist numbers had been consistently higher than last year, except in January and June.

"If the trend continues until year-end, we are optimistic that the Tourism Ministry's target [on tourist numbers] will be achieved," he |said, adding that tourist arrivals usually peaked in December.

Singapore topped the country-of-origin portion in August at 15.13 per cent, followed by China at 14.95 per cent, Malaysia at 11.18 per cent, Australia at 8.35 per cent and Japan at 5.75 per cent.

The data also showed that Bali remained foreign tourists' favourite entry point, although the number of arrivals slid 11.29 per cent year on year to 298,638 and was lower by 21.8 per cent month on month.

Suryamin said the decline was caused by the eruption of Mount Raung in Bondowoso, East Java, which forced Ngurah Rai International Airport in Denpasar, Bali, to close and cancel hundreds |of inbound and outbound flights.

"Most of the tourists then entered the country through Soekarno-Hatta International Airport in Cengkareng, Banten," he said, in reference to data suggesting a 15.5-per-cent increase year on year in tourist arrivals at the Jakarta airport to 252,542 in August, reflecting a 44.2-per-cent jump month on month.

Volcanic activity on Mount Raung shut down international airports serving Surabaya, the largest city after capital Jakarta, and Bali, while other airports serving domestic routes also had to close down temporarily, namely Jember and Banyuwangi in East Java, as well as Lombok in West Nusa Tenggara province.

The natural disaster was also blamed for a decrease in Australian tourist arrivals as their share was slashed to 8.35 per cent in August from 11.54 per cent in July.

"That's a logical consequence, as 80 per cent of Australian tourists entering Indonesia head to Bali," Vinsensius said.